Modulation of periodontal ligament fibroblasts by cementum and alveolar bone extracts

This study investigated the effect of acetic acid extracted proteins of bone and cementum on periodontal ligament fibroblasts. Alveolar bone and cementum obtained from clinically healthy subjects were subjected to 0.5 M acetic acid extraction, dialysis and lyophilization. Effects of both extracts on cell attachment and stimulation of DNA synthesis were studied in fibroblast-like cells cultured from human periodontal ligament tissue. A wide spectrum of proteins, such as 11-14, 17, 19, 22, 24, 27, 30, 34-44, 47 and 55 kDa, were detected in 10% SDS-polyacrylamide gel electrophoresis of both extracts. A few tissue-specific bands (19, 22, 47 kDa in cementum extract; 34-44, 55 kDa in bone extract) were noted. These extracts were found to promote cell attachment and stimulate DNA synthesis of periodontal fibroblasts. Cementum extract appeared to have a higher activity in stimulating DNA synthesis than bone extract, while promotion of cell attachment was similar with both extracts. Addition of serum evoked a synergistic effect on the promotion of DNA synthesis of both extracts. These preliminary observations suggest that acetic acid extracts from bone and cementum contain distinct components capable of modulating cellular activities of periodontal fibroblasts.